Fire Pit Glass and Rocks Buyer's Guide
- Kingsman Tophat Pro
Gas fire pits are the perfect way to liven up your outdoor space and create a focal point for people to gather around. They are easy to operate, low maintenance, and come with several safety features to keep the flames in control.
Customization is another big plus. Between fire glass, rocks, stones, gas logs, and other fire media, you can design the fire display to your liking.
In this article, we'll focus on some of the common types of fire pit media. Fire glass is a very popular option, so we'll cover the different types and sizes and how to know what you should buy. We'll also discuss other media like lava rock, river stone, or decorative pieces like fire logs.
What Is Fire Glass?
Fire glass is rather simple. An (often dyed) pane of glass is tempered to resist the high temperatures. Sometimes a reflective high-temperature laminate is applied after tempering. In some cases, the glass is simply polished instead of laminated. The glass is then broken to the desired size and the pieces are sent through a tumbler to smooth the sharp edges.
Fire glass covers a range of glass fire media that comes in many colors, shapes, sizes, and varieties. In addition to classic broken glass pieces, fire glass also includes smooth glass beads, nuggets, gem shapes, etc.
The following are some examples of options when it comes to buying fire glass:
Classic/Rough – These glass pieces undergo little to no modification after they are shattered. The glass will likely be lightly tumbled to remove any sharp points or edges that could cause cuts or block small gas ports in a burner.
- Amantii Suntea small bead fire glass
Tumbled – Tumbled glass (not surprisingly) spends additional time in a tumbler. Sometimes sand is mixed in to weather the glass and smooth the edges. In terms of smooth edges and shape, tumbled glass falls somewhere between classic cut and glass beads. It is usually available in all the same sizing categories as classic glass except for ¾ inch.
Cut glass – This category is specifically cut into certain rectangular or square shapes. As with classic glass, it is lightly tumbled to remove sharp edges but usually retains its distinctive right angles. While very unique, this glass is more costly due to the additional manufacturing equipment and time that goes into producing it.
- Black fire glass
Fire glass beads or gems – These are smoother, more uniform shapes. The beads have a rounded shape, while the gems are more complex shapes like a diamond.
Why Choose Fire Glass?
- Reflective colors that enhance the flame without fading
- May be used for other projects (i.e. landscaping, flower arrangements, indoor gas fireplaces, etc.)
- Sold in various quantities
- Promotes good combustion
- Withstands exposure to the elements
- May require several bags to fill larger units
- Used primarily to create a more contemporary look
What Sizes Can You Find Fire Glass?
The size of your fire glass makes a difference because it determines how much coverage you can get per pound and can also affect the flow of gas from the burner. Pay attention to the recommended size for your specific fire pit. The common sizes are 1/4", 1/2", and 3/4" glass. You can also buy variable size glass.
- 1/4 inch – This small size is often required or used for applications where the glass can be densely packed without blocking the gas flow. All the tiny pieces give a glittery, sparkling effect. This size is commonly used in smaller gas fireplaces or as an accent in electric fireplace models.
- 1/2 inch – The slightly larger size makes it slightly less dense, so each pound covers more surface area than the 1/4" option. It also allows more gas to flow through. It is often used with pan type burners that have sand or vermiculite as a base material, preventing the glass from blocking burner ports.
- 3/4 inch – This size is usually recommended for outdoor fire pits or other outdoor features. The larger size makes it less likely to block the gas flow, so it works well for high BTU outputs or upward facing gas jets. The low density also offers excellent coverage per pound. (It is rarely used for indoor fireplaces.)
- Red, white, and blue fire glass
- Variable – Usually anywhere from 1/2” to 1” in size, variable sizing adds diversity to the reflective nature of the glass bed and can be used with many gas burners, fire pits, and fire features, but not usually with gas fireplaces.
What Colors of Fire Glass are Available?
- Blue and red fire glass and lava rock
Fire glass comes in a wide range of colors with clear, black, amber, brown, and blue among the more popular options. You also have the option to choose a regular or reflective finish. The reflective fire glass has a mirror finish on one side to create more dramatic flashes of reflection scattered throughout the fireplace to enhance the appearance of the flames.
The color you select plays a huge role in the overall style of your fire pit. Jet black often gives a sophisticated vibe, while neutral browns, whites, or amber might tend more toward a traditional look. Brighter colors like sapphire, green, or red show off an edgy modern style.
- Holding red and white fire glass
Can't decide which color to choose? You may enjoy mixing colors to create your own unique look. You can either mix them uniformly or create patterns with different colors. Either way, the artistic expression is up to you!
And remember, you don't have to stick with fire glass. There are other options like ceramic "river rock" or lava rock that you can use instead (or even combine them with fire glass!)
When To Use Fire Glass
Unlike a set of gas logs that rest on a grate above the burner, fire glass is designed to lay as a bed of media directly over the burner that it is being used with. For this reason, fire glass is intended for use only with certain categories of hearth appliances.
Always use glass specifically designed for use with gas appliances. Using other broken glass or glass objects is dangerous and could melt and ruin your fire pit.
- Amantii 2939 Tru View XL
Electric fireplaces are by far the easiest to incorporate fire glass. They often have a tray at the front of the unit to hold a set amount of glass. Because this area is separate from any of the electric equipment in the unit, it is easy to add more glass or change the color if you wish.
Gas appliances are more complex when it comes to fire glass. Every manufacturer of gas burners or appliances will specify what size, quantity, and exactly where over the burner the fire glass can be placed. Read the product manuals or brochure information to prevent issues from overfilled or improperly installed glass.
Fire pit burners are less sensitive to overfilled or undersized glass since their higher gas flow and BTU outputs help them to power through the glass. Still, lower BTU gas burner sets and gas fireplaces can have difficulty operating if too much glass is placed over the burner. It's also important to know whether or not you can cover the burner at all. Some models are specifically designed for the glass to only surround the burner as an accent, while others are rated for the glass to cover the burner at a certain thickness and density.
When Not to Use Fire Glass
Never, I repeat, NEVER use any type of fire glass with wood burning fire pits, fireplaces, or stoves. The glass is not able to withstand the higher temperatures that wood fires create and could melt and ruin your appliance. And don't ever use regular, non-fire glass in any situation (even for gas appliances).
Lava Stones, River Rock, and Other Fire Media
Looking for something besides fire glass? No problem. There are several other media options that are designed to work well with gas fire pits. Some common choices include fire pit rocks like lava rock and river rock or fire pit rocks with ceramic log sets. You can also use glass beads which have a different look than the typical crushed fire glass.
- Lava rock
Lava rock and lava stones typically come as 1-2 inch pieces. Many people use lava pieces as a base for log sets. As mentioned above, you can also layer lava rock and fire glass to save money on your fire pit display.
- Fiber fire rock
River rock for gas fire pits is not real river rock. (Please do not put ANYTHING in the fire pit that is not specifically designed for safety with gas fires.) Instead, the river rock is made from multi-color ceramic fiber and gives a realistic and rustic feel to your fire pit.
Log sets come in a variety of shapes, styles, and number of "logs". Often used in combination with lava rock or stones, they are made from refractory cement or ceramic fiber.
Unlike the uneven edges of the standard crushed fire glass, fire beads are carefully shaped into uniform round pebbles. You can also find other shaped glass-like diamond or gem-shaped pieces.
- Napoleon fire globe
In addition to fire glass and ceramic fire stones, there are also decorative pieces that fall into the category of fire art. This would include accents like cannonballs (globe-shaped decorations in a variety of colors). Usually, the fire art or accent pieces are used along with a base of fire glass.
In What Quantities is Fire Glass Sold?
Fire glass is sold either by the pound, or square feet, or cubic feet. On our website, you can purchase in very small quantities like one pound, all the way up to 90 pounds. If you find it confusing to calculate how many pounds you will need for your square footage (or vice versa), you might try searching for an online fire glass calculator.
Unfortunately, many of the calculations will be brand-specific, so it's best to look up the company website and see if they have their own fire glass calculator. An example would be this one at American Fireglass.
Ready to start scrolling through the color options? Here are four companies that we recommend when it comes to finding quality fire glass. You'll notice the options are quite broad, so it shouldn't be hard to find something that suits you perfectly.
- American Specialty Glass makes all of its glass products from recycled glass. They carry a large selection of colors and are even able to provide custom colors in certain quantities.
- American Fyre Designs specializes in outdoor fire features. When it comes to gas fire media, they carry more than just fire glass. In addition to several colors of glass, they offer fire gems, fire logs, fire pinecones and acorns, river rock, lava rock, and more.
- Kingsman Fireplaces prides itself on long-term customer satisfaction. Their modest selection of fire accessories includes unique items like cannonballs in addition to common media like lava rock or log sets.
- Empire Comfort has been a family-owned company since 1932. Their fire glass comes in a wide range of colors, along with different shapes and styles.
How Much Decorative Media Should You Add?
The amount and size of decorative media you will need is dependent on the specific model of your fire pit. There are so many variables with BTU output, size, burner type, and application that there is not a one-size-fits-all formula. Review your fire pit (or fire pit burner) owner's manual to find information on what you will need.
Outdoor fire pits have an added layer of complexity because they are so deep. Filling the cavity of a large fire pit takes a crazy amount of fire glass. A much less expensive option is to fill the inside of the fire pit with lava rock and then layer the glass on top. This gives the illusion that the entire pit is fire glass, without the extra cost.
- Hearth Products Controls fire pit ring with lava rock and gas logs
In many cases, the recommendation is to fill the area below the burner with lava rock up to the level of the burner gas ports. From there, you can consult the manufacturer's specifications for how much glass should cover the burner. If that information is not available, you can estimate the area by measuring the height from the top of the burner to the top of the enclosure.
Some fire glass calculators like this one from American Fyre Designs account for substrate (lava rock) depth in their calculations.
Each manufacturer of fire glass is different, so use their recommended volume for covering a certain number of square or cubic feet. Many of the companies offer an online calculator but keep in mind that the calculations are only for that brand of fire glass.
Care and Maintenance
If your fire glass starts to lose its shine, you can wash it in a bucket of soap and water or with distilled water and vinegar. Simply add it to the bucket, rinse, and spread out to dry. If your lava rocks are exceptionally dusty, you can remove them and spray them off with a hose.
Fire glass for residential fire pits will usually ship via small parcel posts like FedEx, UPS or USPS. Extra-large orders, such as ones from corporations ordering decorative media for multiple fire pits may ship via freight.
- Round fire pit with blue fire glass
Fire media is part of the fun of a gas fire pit. You have so much control over the color, style, and design. Fire glass, fire beads, lava stones, river rock, log sets, and fire art can be selected or combined for a look you love.
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Fire Pit Glass and Rocks Q&A with the NFI Certified Specialists* Please Note: All customer questions are answered by our NFI Certified Specialists free of charge!
from Colomial Heights, VA asked:
August 6, 2021
I want the lava rocks to cover the shiny burner. Is this ok or should the burner be exposed with the rocks around?
Please consult your owner's manual for your specific fire pit. Many times the burner will need to be left exposed.
on August 9, 2021
from Ohio asked:
May 24, 2021
Can you put fire glass over lava rocks?
In most cases, yes, a gas fire pit can utilize a lava rock base with fire glass on top.
Tyler M. - NFI Master Hearth Professional
on May 24, 2021
from Waltham, MA asked:
May 19, 2021
Can I use stones instead of glass in my fire pit?
It is recommended to use the material that is approved in your owners/installation manual.
on May 19, 2021
from Owensboro, KY asked:
February 26, 2021
How much fire pit glass do I need to buy for a 144 square inch fire pit area?
A 10 lb. bag covers 1/2 sq. ft. area with depth of 1", so the total amount needed would vary depending on the depth that your firepit needs.
on February 26, 2021
from Massachusetts asked:
September 24, 2020
Could I use the fire pit glass/rocks instead for my wood burning fire pit?
Lava rocks and fire glass are used with gas-burning fire pits, not woodburning.
Tyler M. - NFI Master Hearth Professional
on September 24, 2020
from Sarasota, FL asked:
July 10, 2020
Is there any problem with us using glass instead of the stone that came with the fire pit?
Many fire pits will allow the use of fire glass
as a replacement for the stones. Check your owners manual for verification.
on July 10, 2020